function s1_gennerate_a_series_of_files(){
       for i  in {1..100};
       do 
      echo $i>/tmp/new_file$i;
       done
}
function s2_list_4_files_in_long_format_about_account_and_group(){
       ls -l /etc/{passwd,shdow,group,gshaadow}|sort
function s3_find_items_related_to_given_username(){
        grep -h $1/etc{group,shadow}| sort
}
function s4_find_items_relasted_to_given_group_name(){
     grep -h $1/etc{group,gshadow}|sort
}
function s5_crete_groups_for_given_group_names(){
       groupadd rnd
       groupaadd itoperation
}
function s6_create_users_and_set_their_group_as_requiired(){
        useradd aadam
        useradd bob
        useradd calvin
        useradd david 
        useradd edwaard 
        usermod  -a -G rnd adam
        usermod  -a -G rnd bob
        usermod -a -G rnd edward
        usermod -a -G itoperation calvin
        usermod -a -G itoperation daavid
}
function s7_change_user_shell(){
       usermod -s /usr/bin/sh adam
       usermod -s /usr/bin/sh edward
}

function s8_set_password_change_policy(){
   passwd -n 10 -x 60 -x 10 adam
   passwd -n 10 -x 60 -w-10 bob
   passwd -n 10 -x 60 -w 10 david 
   passwd -n 10 -x 60 -w 10 calvin 
   passwd -n 10 -x 60 -w 10 edward
}

function s9_set_password_for_five_user(){
   usernames=(adam bob calvin david edward)
   password=("$1""$2""$3""$4""$5")
   for i in $(seq 0 4);do 
   echo "${usernames[$i]}:${passwords[$i]}"|sudo chpasswd
   done
}

function s10_lock_bobs_password(){
 usermod -L bob
}

function s11_include_adam_into_wheel_group(){
  sudo usermod -a -G  wheel adam
}

function s12_change_files_permission(){
   for i in {1..100};
    do 
     filename="/tmp/new_file${i}"> $filename
      if (($i % 3 == 0));
     then
         sudo chmod 640 $filename
         fi 
      done
}
}
